Hyundai Tiburon Forums banner
1 - 4 of 4 Posts

·
Registered
Joined
·
2 Posts
Discussion Starter · #1 ·
2006 Tiburon 140K miles, 2.0L auto. Good operational condition. Had P0133 (slow to respond) and I replaced the upstream sensor with a BOSCH part. The previous owner also replaced the O2 sensor.
The CEL came on 50 miles later. I was suggested this thread:

Based on info there and in a couple other threads, it seems many owners induced the error by adopting aftermarket exhaust headers. This moves the O2 sensor at least 3' further down , where it is cooler. Their only solution was to revert to stock.
Some of the other sufferers were do to an exhaust leak at the flex pipe. Most said it came on at 60 mph. Light load, high rpm. Which led to reduced exh temp. My CEL occurred at 60 mph too.

As an electrical engineer I discarded the wire length theories. A few milli-ohms or volts wont matter.
One O2 website said that the response times increased as the temperature dropped.
Another said that typically, the ECU waits 120 ms for a change in the O2 reading after a fuel adjustment.

One poster mentioned a 'tin foil' trick. Another header wrap. To insulate the exh header from cooling outside air.
I had some copper flashing and wrapped a piece around the sensor body. I covered the exhaust header heat shield with a layer of 20 gauge(?) copper. Only the exposed portion facing the radiator.

After 125 miles, and the last half at 60 mph, the CEL has not come on.
 

·
Premium Member
2006 Hyundai Tiburon SE
Joined
·
1,363 Posts
You made a mistake by using Bosch for your O2 sensors. They are known to cause weird issues with our cars. Swap it out for an OEM sensor. NTK, Denso or Mando are acceptable brands.
 

·
Registered
Joined
·
2 Posts
Discussion Starter · #3 ·
You made a mistake by using Bosch for your O2 sensors. They are known to cause weird issues with our cars. Swap it out for an OEM sensor. NTK, Denso or Mando are acceptable brands.
Thanks but the problem preceded the BOSCH. The O2 I took out was a recent replacement, came out easy and was clean. ie new. Had the same error. after clearing the CEL, it would come back on, 1st time on the highway.
 

·
Premium Member
2006 Hyundai Tiburon SE
Joined
·
1,363 Posts
What brand was the first sensor before you replaced it with a Bosch sensor?

The slow response code is very typical on aftermarket O2 sensors such as Bosch or Walker brands. The OEM acceptable brands like NTK, Denso and Mando don't have that issue. This is a known problem that dates back 20+ years.

Don't get me wrong. Your approach is unique and seems to work well. But you've over engineered a problem that you didn't need to. I know because I am an Engineer in a similar field and tend to do the same.
 
1 - 4 of 4 Posts
Top